1 Exploration of the bimetallic composite technology of the oil cylinder

When the movable cylinder is working, it extends ~2/3 of the oil cylinder, which is easy to corrode and bend, making the dust ring work in poor condition, resulting in A vicious cycle brings dust and impurities into the oil cylinder as the movable cylinder extends and retracts, seriously affecting the sealing of the piston Y-ring. The coating of the oil cylinder falls off, the gap becomes larger, and the seal cannot effectively seal. At the same time, due to the overdue service of most of them, pits appeared on the surface of the cylinder cylinder. For the above situation, use the method of re-coating, or spray the inner wall of the oil cylinder with wear-resistant or plastic powder. However, if the gap is too large, copper plating cannot solve this problem, and the spraying process is often affected by various factors. The sprayed layer is easy to fall off, and the hardness and impact resistance of the plastic powder are not good, and the stainless steel lining The process can handle the over-tolerance gap O. Cylinders within 8 mm are repaired. After the sleeve treatment, the surface hardness and roughness are increased, and the wear resistance and corrosion resistance are improved, which increases the service life of the single hydraulic prop and eliminates the danger of corrosion of the inner wall of the cylinder in the future.

1.1 Selection of lining materials

The material is austenitic stainless steel with a thickness of 0.6~0.8ram, which has good plasticity, toughness, process performance, and durability. It has the characteristics of strong corrosiveness, especially the significant improvement of welded parts, due to the welding knife-like corrosion caused by the use of stabilizing elements. For example, for stainless steel made of 1Crl8Ni9, 0Crl8Ni9Ti, 1Crl8Ni9Ti, etc., the tensile strength of the weld after welding is more than 1.5 times that of the raw material, and the elongation is greater than 26%. Using it as a bushing solves the problem of surface treatment of the inner hole of the oil cylinder. In comparison, the coating thickness of chrome plating, copper plating and other processes is only 25~30¨m, which is far inferior to the composite stainless steel sleeve in the inner hole of the oil cylinder.

1.2 Problems that need to be solved when composite technology is applied to cylinders

The first is the welding process. For stainless steel with a thickness of only 0.6~0.8mm, it is extremely easy to If welding deformation occurs, the weld must be smooth and flat, and must withstand a pressure test of 42Mpa, and ensure no leakage within 2 minutes, and the weld must be eliminated to make it as smooth as a mirror. The second step is how to inlay and assemble the welded stainless steel bushing to the inner wall of the oil cylinder and the outer wall of the injection column, and the fit must be tight to ensure that the size is within the range of 10OMPa.

2 Process flow of monomer inlay

2. 1 Stainless steel lining composite process.

When butt welding, argon gas protection is used for automatic welding, so that the welding speed is uniform and the welding quality is good; the rolling repulsion method is used in the welding seam treatment, so that firstly, the welding can be made smoother, and secondly, it can Eliminate stress caused by welding.

2_2 Oil cylinder repair process

In spinning lamination, a special tooling of 6 simultaneous rolling spinning is used, which can cause the bushing to plastically deform and be tightly rolled and adhered. When combined on the oil cylinder, it is integrated and forms a composite oil cylinder. After spinning, the welding of the bushing is very smooth and flat, which can be seen but not touched.

3 Conclusion

The service life of the oil cylinder is extended by 3 to 5 years, which greatly reduces the scrap rate. The pressure stabilization is reliable during use, and the leakage failure rate is 5%, which is within the normal range and has a relatively high performance. High economic benefits.